Gas burner and pilot means therefor



m K "m A GAS BURNER AND PILOT MEANS THEREFOR Filed Oct. 26, 1949 r J w WV nflmm G, 0 UJ n 1 W %9. 7%, \w

United States that E Kid *3? Fatentedl h'iay 3i, l iili GAS BURNER AND PILOT MEANS TmREFOR Adrian .l. Kilt, Holland, Mich.

Application October 26, 1949, Serial No. 123,673

9 Claims. (Cl. 158-439) My invention relates to an improvement in main gas burners and in pilot means therefor.

One purpose is to provide a burner assembly adapted for silent ignition.

Another purpose is to provide a burner assembly adapted for silent extinguishing.

Another purpose is to provide for improved means for controlling the flow of gas to the main burner and pilot light or burner of a gas burning assembly.

Another purpose is to provide means for shutting off and preventing passage of gas in the event of pilot flame failure.

Other purposes will appear from time to time in the course of the specification and claims.

I illustrate my invention more or less diagrammatically in the accompanying drawings wherein:

Figure l is a schematic layout of a structure embodying my invention, including parts in elevation and an associated diagram;

Figure 2 is a side elevation, with parts broken away and parts in section, of a main burner valve control assembly; and

Figure 3 is a sectional view of one of the valves shown in Figure 1.

Like parts are indicated by like symbols throughout the specification and drawings.

Referring to the drawings, 1 generally indicates a gas supply pipe or line extending to any suitable source of gas, such as a conventional gas main. 2 is a main burner supply branch, and 3 is a pilot supply branch. 4 indicates a main burner valve assembly, and 5 a pilot valve assembly, each with its solenoid 4a and 5a, respectively. As illustrated in Figure 3, pilot valve 5 is of a type allowing passage of a small amount of gas or fuel when the solenoid 5a is deenergizcd. It may include, for example, passages 5b and 5ccommunicating' through a valve seat 5d, which is closed by a plug 5e when solenoid 5a is deenergized. Plug 5e may be biased'toward closing position by a spring 5 and may be raised by energization of the solenoid 5a. A relatively small bleed passage 5g may establish communication between the passages 51; and 5c independently of the valve seat 5d to provide a low pilot flame. Energization of solenoid 5a raises the valve plug 5e to permit a substantially increased flow of gas to the pilot burner. i wish it to be understood that there are many equivalent forms of valves operating in this manner and the showing in Figure 3 should be taken as illustrative. 6 is any suitable main burner, the details of which do not form part of the present invention, and 7 is any suitable pilot burner.

It will be understood that the showing of Figure 1 is diagrammatic, and that, for example, the main burner 6 and the pilot burner 7 are diagrammatically or schematically shown, it being the intention that a suitable pilot structure is employed in which a pilot nozzle, such as the nozzle indicated diagrammatically at 7, may normally burn with a low flame, when the main burner 6 is extinguished, but, at the time of lighting, and only at the tit time of lighting, is caused to burn with a larger flame or flare which extends to or surrounds, or closely approaches, the main burner d.

Referring to Figure 2, the valve stem 10 of the valve assembly 4 for the main burner 6 is shown as carrying a small cam or projection 11 which is positioned to trip a mercury switch 12 mounted upon any suitable support 13 and normally held in an intermediate or horizontal position, for example, by the springs l4. Springs 14 bias the switch 12 toward the horizontal position as shown in Figure 1. As will be seen in Figures 1. and 2, the cam It will trip the switchlZ as long as the cam is in contact with switch 12. When the cam has moved upwardly a suflicient distance to move out of contact with the switch, the springs 14 return the switch to the intermediate position. Whereas I have shown in Figure 2 an upright cam or projection 11, it will be understood that if a rotating valve stem is employed, a corresponding cam would be extended around the entire circumference of the stem. 15' is a solenoid coil, shown in Figure 1, adapted to operate the main valve stem it and i6 is a solenoid coil, shown in Figure 1, adapted to operate the pilot burner valve stem Ma. 1] is any suitable house thermostat with its fixed contact tilt and its movable contact 19, which may include a bimetal or other suitable unit, responsive to changes in ambient temperature. Whereas my unit is shown as designed primarily for residence gas furnaces, my controls can also be applied to other appliances in domestic, industrial or commercial use. They may also be adapted, or applied, in part or in whole, to existing in stallations. 2t) generally indicates a main transformer, and 21 a lighter switch. 22 is an igniter transformer.

As will be clear from the diagrammatic showing of Figure 1, when the house thermostat 17 calls for heat, it closes the contacts 18 and 19, thereby energizing the solenoid coil 15 and slowly moving the main burner valve stem Ill toward the open position provided the pilot is burning, to thus close the circuit at 26-27. The result of its movement toward open position is to engage the cam 11 with the switch 12, to energize the pilot solenoid coil 16. This opens the pilot valve and causes flame to flare from the pilot nozzle 7.

The main burner valve solenoid coil 15 can only be energized if a pilot light is burning at the nozzle 7. The pilot light is first ignited by closing the starting switch 21, and thereafter normally burns at a low flame. The flame may be adjusted, for example, by an adjusting screw or control 25. The circuit through the main solenoid coil 15 and the thermostat 1'7 is closed only when the contacts 26 and 27 are engaged. If flame should fail, the bimetal 25 will shut off all gas, and, at the same time, will break the circuit between 26 and 27, thereby preventing any raw gas from flowing to the main burner, because the main valve iwill be closed. It will be understood, also, that there is no gas flow at that time to the pilot, valve 36 being then closed by thermostat 26. The action of the main burner valve, as shown in Figure 2, may be slowed down and governed by the use of any suitable dash-pot or air chamber 23, in which any suitable piston or plunger may move, mounted on the stern ll). 29 indi cates any suitable orifice, which may be fixed, or, if desired, may be made adjustable. The springs 14 are adapted to return the pilot switch to the off position after opening of the main valve.

56) diagrammatically illustrates any suitable furnace temperature limit control, the details of which do not, of themselves, form part of the present invention.

It will be realized that, whereas I have described and illustrated a practical and operative device, nevertheless many changes may be made in the size, shape, number and disposition of parts without departing from the spirit of my invention. I therefore wish my description and drawings to be taken as in a broad sense illustrative or diagrammatic, rather than as limiting me to my precise showing.

The use and operation of my invention are as follows:

The pilot may be lighted by closing the lighter switch 21. The result is to deliver current through the igniter resistance 35. This warps the bimetal 26 sufliciently to permit gas to begin to flow through the shut-off valve 36. The gas thus released is ignited by the resistance 35, and causes the bimetal 26 to warp into conductive contact with the normally fixed contact 27. At the same time, contact with the switch 27a is broken, and the holding magnet 21a of the wiring switch is deenergized, and no further current flows through the resistance 35. It will be understood that the movable element 21b of the arc switch 21 is released.

Thus the initial result of closing the starting switch is to ignite the pilot flame, and a small flan-1e thereafter burns at the pilot nozzle 7.

Assume that the thermostat 17 then calls for heat. When the contacts 18 and 19 are closed, a circuit is closed through the solenoid coil 15, and the result is a movement of the main valve stem it toward the open position, which permits gas to flow to the main burner 6. At the same time, the rise of the stem 1t closes a circuit through the contacts 12a and 12b of the switch 12, and the solenoid coil 16 of the pilot valve assembly 5 is thereby energized. Whereas I have shown a mercury switch, I do so as a matter of illustration. but other types of switches or mechanically controlled valves may be employed. The result of the above described action is the passage of a substantially increased gas supply to the pilot nozzle 7, and, at about the time that gas flows from the main burner, a flare of gas is delivered also from the pilot burner. This insures an im mediate ignition of the gas supply to the main burner, and prevents popping or noise which results if there is any delay in the ignition of the main gas supply. The spread of flame of the flare from the pilot nozzle is suflicient to insure immediate and silent ignition of the main gas supply. When the cam 11 has fully passed the switch 12, the springs 14 return the switch to its intermediate position, thus deenergizing the coil 16 and returning the flame at the pilot nozzle 7 to the low point. solenoid 5a is energized for a predetermined period of time as governed by the contact of the cam 11 with the switch 12, and an increased flame at the pilot burner results for the same period of time.

When the thermostat ceases to call for heat, then a dash-pot effect of the dash-pot housing 23 and the aperture 29 causes a gradual cutting down of the supply of gas to the main burner, and it gradually becomes extinguished.

It will be observed that unless the pilot flame is burning at least at its minimum fire, no gas can pass through the main valve assembly 4 to the main gas burner d. If the pilot burner is extinguished, then the warping bar 26 warps back to the position in which it is shown in Figure 1, closing the valve assembly 36 and making it impossible to energize the coil 15.

It will be understood that, in the illustrated mechanism, the dash-pot structure 28, 29, with the stem and plunger structure 10, 23a control both the opening and theclosing rate of the main burner valve. These, plus the cam switch and their relative position, retermine the amount of'gas, and thereby the mixture, available at the main burner at the time of flaring of the pilot flame. it will be further understood that the control of the rate of opening of the main burner valve may also be obtained by varying the solenoid field, by a servo mechanism or by any other suitable means.

I claim:

1. In a control assembly for gas burners, a main gas burner, a pilot gas burner adjacent the main gas burner,

A mercury switch is preferable,

Thus the 3, formed and positioned to deliver a flare of flame thereto, gas supply pipes extending from a suitable gas supply source to the main gas burner and to the pilot gas burner espectively, a valve for the main gas burner supply pipe and electromagnetic means for actuating it, valve means for supplying gas to the pilot burner which when ignited provides normal pilot flame, a separate valve for the pilot gas burner supply pipe to deliver an excess supply of gas thereto when said valve is opened, and separate electromagnetic means for actuating said separate valve, and means for actuating the electromagnetic means of said separate pilot valve to open same in response to mechanical movement of the main burner valve toward open position to deliver excess gas to the pilot burner when the main burner valve is opened whereby to ignite the main burner by the resulting flare of flame at the pilot burner.

2. The structure of claim 1 characterized by and including a switch in circuit with the electromagnetic means for actuating the pilot valve, and a mechanical actuating connection between the switch and the main valve.

3. In a control assembly for burners, a'rnain burner and a pilot burner adjacent the main burner, fuel supply ducts connecting the main burner and the pilot burner to a supply of fuel, means for establishing a normal pilot flame at the pilot burner, an excess supply valve in the line of fuel flow to the pilot burner for increasing the intensity of burning of said pilot burner, a main fuel supply valve in the line of fuel flow to the main burner, a temperature sensing element adapted to activate a valve opening and closing mechanism for the main supply valve, and a valve actuating mechanism for the excess supply valve adapted to be actuated by movement of the main valve toward open position.

4. A control assembly as in claim 3 wherein said excess supply valve actuating mechanism is actuated after a predetermined period of time following the actuation of said valve actuating mechanism for the main valve.

5. In a control assembly for fuel burners, a main burner and a pilot burner adjacent the main burner, fuel supply ducts connecting the main burner and the pilot burner to a supply of fuel, means for establishing a normal pilot flame at the pilot burner, an excess supply valve in the line of fuel flow to the pilot burner for increasing the intensity of burning of said pilot burner, a main supply valve in the line of flow of fuel to the main burner, an electromagnetic valve actuating mechanism for said main valve, an energizing circuit therefor including a thermostatic switch element adapted to make and break said energizing circuit in response to a temperature to be controlled, electromagnetic means for operating said excess valve, and an energizing circuit therefor including normally open switch means for completing said second mentioned energizing circuit, and means operatively associated with said first mentioned electromagnetic valve operating means to close said normally open switch means a predetermined time after initial movement of said main valve toward open position.

6. In a control assembly for burners, a main burner and a pilot burner adjacent the main burner, fuel supply ducts connecting the main burner and the pilot burner to a supply of fuel, a first supply valve in the line of fuel flow to the pilot burner, a second fuel supply valve in the line of fuel flow to the main burner, solenoids adapted to. be connected to a source of electrical energy and adapted to open and close said valves, a first temper ature responsive member for establishing a connection between the source of electrical energy and said solenoid for the second valve, means responsive to the movement of said second valve to an open position for energizing the solenoid of the first named valve, and a second temperature responsive member positioned adjacent said pilot burner for establishing an electrical connection between said source of electrical energy and said first named temperature responsive member in response to production of the pilot flame whereby extinguishment' of said pilot burner renders said first named temperature responsive member ineffective.

7. In a control assembly for gas burners, a main burner, 21 main gas valve, a pilot burner, means to establish a low flame at the pilot burner, a pilot gas valve adapted when actuated to supply an excess of fuel to the pilot burner, a valve stem for said main gas valve, electromagnetic means for moving said stern to open the main gas valve, a cam on said stem, a switch positioned to be actuated by said cam when said stem is moved, and electromagnetic means in circuit with said switch for actuating the pilot gas valve to open position in response to movement of the main valve to open position to thereby create a flash of flame at the pilot to ignite the main burner.

8. The structure of claim 7 characterized by and including a heat responsive switch subject to the heat of the pilot flame in circuit with the electromagnetic means for moving the stem of the main gas valve, said heat responsive switch including an element movable to circuit breaking position when the pilot burner is out.

9. In a control assembly for gas burners, a main burner, a pilot burner adjacent the main burner, supply pipes extending from a suitable gas supply to the main burner and to the pilot burner, a main burner supply valve, a normal pilot gas supply valve, thermostatic control means for the normal pilot gas supply valve responsive to heat from the pilot burner when ignited to maintain normal pilot flame, an excess gas pilot supply valve, means for normally holding said pilot excess supply valve at minimum flow position, and means for opening the pilot gas supply valve for a predetermined limited period in response to opening of the main burner supply valve to ignite the main burner by flare of flame from the pilot burner resulting from the excess gas supplied thereto.

i telerenees Cited in the file of this patent UNITED STATES PATENTS 1,533,094 Buehler Apr. 14, 1925 1,629,251 Blake May 17, 1927 1,668,251 Ryon May 1, 1928 1,670,741 Ray May 22, 1928 1,675,133 Rayfield June 26, 1928 1,858,505 Jacobi May 17, 1932 1,874,710 Persons Aug. 30, 1932 1,894,900 Victor Jan. 17, 1933 1,968,319 Shively July 31, 1934 1,995,846 Gauger Mar. 26, 1935 2,138,796 Sparrow Nov. 29, 1938 2,152,790 Clark Apr. 4, 1939 2,200,908 Beggs 1- May 14, 194-0 2,210,853 Falkenberg Aug. 6, 194-0 2,549,633 Ottmar Apr. 17, 1951 

